Primary references

• Oppel, N. 1811. Die Ordnungen, Familien und Gattungen der Reptilien, etc. Lindauer: Munich.

Additional references

• Parkinson, C.L. 1999. Molecular Systematics and Biogeographical History of Pitvipers as Determined by Mitochondrial Ribosomal DNA Sequences. Copeia 1999(3): 576–586. DOI: 10.2307/1447591 Reference page. 

• Campbell, J.A. & Lamar, W.W. 2004. The Venomous Reptiles of the Western Hemisphere. 2 Volumes. Cornell University Press: Ithaca, New York. 1032 pp. ISBN 9780801441417 Reference page. 

• Castoe, T.A. & Parkinson, C.L. 2006. Bayesian mixed models and the phylogeny of pitvipers (Viperidae: Serpentes). Molecular Phylogenetics and Evolution 39(1): 91–110. DOI: 10.1016/j.ympev.2005.12.014 Reference page. 

• Fenwick, A.M., Gutberlet Jr., R.L., Evans, J.A. & Parkinson, C.L. 2009. Morphological and molecular evidence for phylogeny and classification of South American pitvipers, genera Bothrops, Bothriopsis, and Bothrocophias (Serpentes: Viperidae). Zoological Journal of the Linnean Society 156(3): 617–640. DOI: 10.1111/j.1096-3642.2008.00495.x.Reference page. 
• Guo, P. & Wang, Y. 2011. A new genus and species of cryptic Asian green pitviper (Serpentes: Viperidae: Crotalinae) from southwest China. Zootaxa 2918: 1–14. Preview

• Alencar, L.R.V., Quental, T.B., Grazziotin, F.G., Alfaro, M.L., Martins, M., Venzon, M. & Zaher, H. 2016. Diversification in vipers: Phylogenetic relationships, time of divergence and shifts in speciation rates. Molecular Phylogenetics and Evolution 105: 50–62. DOI: 10.1016/j.ympev.2016.07.029 Reference page.